Color mixing basics – basic paint and color paste
I. Basic Paint
The so-called basic paint, in simple terms, is the white paint or varnish produced by the paint enterprises themselves (does not contain pigments for covering power). Base paint is the carrier of color mixing, and the control of base paint in the process of color mixing will affect the accuracy of color mixing, reproducibility, compatibility, economy and color gamut coverage in all aspects. At the same time, the base coat is the only part of the integrated color mixing system in the factory store that is prepared by the paint company itself, and therefore different base coats make a significant difference in the use and effect of the color mixing system. The basic paint due to its different formulations, the use of different ranges, there is a big difference, in order to improve the manufacturers of the basic paint in the integrated color mixing system when the use of matching and give full play to the advantages of the system, the need to adjust the basic paint.
(A) the batch color difference of the basic paint on the color mixing system
Enterprise production of basic paint, if the product batch is different, there will be a color difference between the batches of basic paint. These color differences, will cause the color results have a great deviation, experiments have proved that, due to different batches of basic paint coloring results of the comprehensive analysis, the color difference of the basic paint needs to be controlled at 0.3 or less, the final results of the coloring system will have less impact.
(ii) The effect of the compatibility of base paint and color paste on the final results of the color mixing system
The compatibility of the basic paint and color paste affects the accuracy and economy of color mixing, good or bad compatibility can be seen through the finger study test and mix the color paste with the basic paint and leave it for a long time after mixing.
The so-called finger research test, that is, take 100 g of white paint, add 2 ~ 3 g of color paste to be tested, fully stirred, coated on the surface of the coated object, when the paint film is about to dry, with a finger to grind the surface layer of the film part of the paint film to be dry, to be dry, to observe the finger research and rubbed and un-researched place whether there is a color difference, such as the difference is large, then the color paste is not good with the compatibility of the paint under test, the color paste of this color mixing of paints is prone to produce floating color phenomenon. If the difference is big, the color paste is not compatible with the tested paint, and the paint made from this paste will be easy to produce floating color. If the color is the same, generally does not produce floating color phenomenon.
Experiments have proved that when the compatibility of the finger study color difference is below 0.5, the accuracy and economic impact on the final results of color mixing are small.
The color paste and the basic paint mixing method, that is, add the selected color paste into the basic paint, stirring and mixing, static 24 h, to observe whether the phenomenon of floating color (pigment stratification), such as the appearance of pigment stratification, it shows that the use of the color paste and the basic paint compatibility is not good.
(C) The influence of the division of titanium white content of the base paint on the color mixing system
The division of titanium dioxide content in the basic paint is mainly based on the requirements of color mixing on the color gamut and economic requirements, as well as the requirements of the paint on the covering power and the maximum additive amount of the color paste on the performance of the paint and so on. These aspects of the factors must be considered comprehensively before making a reasonable division.
There are many ways to divide the titanium dioxide content in the base paint that can satisfy the color gamut coverage and economy, and now there are 4 kinds of titanium dioxide content of the base paint system and 2 kinds of titanium dioxide content of the base paint system in common. However, after comprehensive consideration of economy, color mixing cost, inventory savings and other comprehensive factors and market demand for color, according to the actual situation of the enterprise itself, to determine the division into the number of titanium dioxide content of the basic paint system composed of the number of titanium dioxide content. For example, a system of basic paint is divided into three kinds of titanium dioxide content, respectively, A paint titanium dioxide content of 18% to 23%, B paint titanium dioxide content of 7% to 13%, C paint titanium dioxide content of 0.
(D) Performance indexes of basic paint
In order to get satisfactory final color mixing results, so that the influence of the base paint on the color mixing results to the extent acceptable to the customer, the requirements of the performance indicators of the base paint, listed in Table 1.
Requirements for the performance indicators of the base coat
Second, color paste
The color paste here, mainly refers to water-based color paste. Water-based color paste refers to organic or inorganic pigments in the surfactant wetting, dispersing effect (can also be added to water-soluble resins), the formation of uniform, stable, with a certain mobility or thixotropic mobility, have a strong coloring strength of concentrated pigment paste. There are two kinds of water-based color paste system: one is high pigment content without resin system; the other is low pigment content with resin (general-purpose resin, other single resin) system. The former has high pigment concentration, strong coloring power, good color spreading performance, good compatibility, thixotropic fluidity, generally does not cause floating color and blossom, and reasonable choice of additives, and has generality. The latter pigment concentration is relatively low, but with good coloring power, good color development, mobility and viscosity is more stable, the system contains resin, compatibility needs to do the test, otherwise it is easy to lead to the paint floating or blooming. The color mixing of oil-based paint generally adopts the pigment paste ground by the enterprise itself.
(I) Requirements of the color mixing system on the color paste and the influence of the color paste on the system
Color paste as a coloring body, in the integrated color mixing at the same time influence
